1. Field of the Invention:
The present invention relates to an automatic gear change device for controlling the operation of a gear transmission and a clutch in an automotive vehicle.
2. Description of the Prior Art:
One example of automatic gear change devices of the type described is disclosed in Japanese patent laid-open publication No. 61-192954 in which two actuators for manipulating a clutch and a gear transmission are controlled based on the control signals issued from a single control unit. The control unit is mainly composed of a microprocessor operable to determine the control signals based on input signals representing various travelling condition data including the vehicle speed.
The disclosed device is disadvantageous, however, in that the control unit and the actuators have a low compatibility with the corresponding components in an automobile of a different type.
With this difficulty in view, a somewhat successful device has been proposed in Japanese patent application No. 61-154339 filed by the present assignee. The proposed device includes an actuator operation control unit which takes over a portion of the function of the conventional main control unit, and a main control unit for controlling the actuator operation control unit, the actuator operation control unit being disposed adjacent to each actuator for controlling the operation of the latter.
The foregoing device is still unsatisfactory, however, in that since the actuator operation control units are connected to the main control unit by exclusive connecting lines, they are likely to runaway when the exclusive connecting lines are damaged or broken away.